Pitfalls in Reasoning
Of all the bias errors in clinical reasoning, two of the most influential on physicians are anchoring and attribution. Bound-ed rationality—the failure to continue considering reasonable alternatives after an initial diagnosis is reached—is also a pitfall. The difference between the latter and anchoring is whether the clinician adjusts the diagnosis when new data emerge.
Anchoring errors may arise from seizing the first bits of data and allowing them to guide all future questioning. “It happens every day,” says Dr. Feinbloom. “The diagnosis kind of feels right. There is something about the speed with which it comes to mind, the familiarity with the diagnosis in question, [that] reinforces your confidence.”
Dr. Feinbloom teaches his young trainees to trust no one. “I mean that in a good-hearted way,” he says. “Never assume what you’re told is accurate. You have to review everything yourself, interview the patient again; skepticism is a powerful tool.”
With the woman who was ultimately diagnosed with Zollinger-Ellison syndrome, Dr. Li’s skepticism paid off—and the hospitalist team benefited from deconstructing its clinical thinking to see where it went awry.
“If someone had gotten the gastrin level earlier,” says Dr. Feinbloom, “they would have caught it, but it was not on anyone’s radar. When imaging was negative, the team assumed it wasn’t a tumor.”
There are lots of lessons here, says Dr. Feinbloom. “You could spin it any one of five different ways with heuristic lessons, but what jumped out at me was that if you don’t know it, you don’t know it, and you can’t diagnose it,’’ he says. “And that gives you a sense of confidence that you’ve covered everything.”
No one had a familiarity with the subtle manifestations of that diagnosis until Dr. Li stepped in. “One lesson is that if you think the patient is on the up and up, and you haven’t yet made a diagnosis,” says Dr. Feinbloom, “it doesn’t mean there’s no diagnosis to be made.”
Dr. Li gives this lesson to his students this way: You may not have seen diagnosis X, but has diagnosis X seen you?
Andrea Sattinger is a frequent contributor to The Hospitalist.
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